@Sorcerersupreme0306 asked: In your Solstice and Eclipse story, have you ever thought of (L/N) accidentally going berserk or on a rampage in a way?

To answer your question simply; he already has.

Understand that (L/N)'s entire story is of someone who doesn't have control of his quirk. Who he is, the way he behaves and interacts with people and the world in general, is because he has, in the past, lost control of his quirk and hurt people. It is through a combination of these events and the way people have responded to them that shapes his character and drives the story's narrative. At this point in time (Book IV), (L/N) still doesn't have full control of his quirk. 

If what you're asking is, in the future, will (L/N) lose control for an extended period of time, thus resulting in damage to people and property, the answer is a resounding no. The reason being that it doesn't serve a narrative purpose. In fact, having this happen would completely undo all of the character development that's occurred over the past three books.

So far, we've explored the damage that losing control of his power has had on his life. Remember that (L/N)'s story is of someone who doesn't have control of their quirk, and because of that has been abandoned by the people he loves and been broken by that rejection. The story is about him recovering from those traumas and about how Yaoyorozu's love helps him to heal. And it is also a story of him eventually gaining control of his quirk and becoming a hero.

While I ended Book III with him losing control again, it was for a very brief moment and it was done for character development, not spectacle. I've spent a lot of time illustrating how he has been slowly gaining control of his power and learning to open up to another person after being hurt so many times. If I were to have him rampage, it would undo all the work I've put into his character. It would tell the audience that he hasn't actually gained any control, and more importantly, it would destroy him as a person.

The scene at the end of Book III is used to mirror what happened with Kendo, except this time he isn't abandoned. Yaoyorozu accepting him and loving him despite the fact that he hurt her is meant to bring them closer together and to allow (L/N) to come out of his shell more. But if I were to have him lose control to the point where he is causing significant damage and harm, it would result in him losing hope entirely and ultimately, it would be the end of his story.